Camila da Silva Rodrigues1, Iana Lamadrid Aurélio1, Marina da Rosa Kaizer2, Yu Zhang2, Liliana Gressler May3. 1. Post-Graduate Program in Dental Science, Federal University of Santa Maria (UFSM), 1184 Floriano Peixoto, 7th floor, 97015-372, Santa Maria, RS, Brazil. 2. Department of Biomaterials and Biomimetics, New York University, 433 First Avenue, 8th floor, 10010, New York, NY, USA. 3. Department of Restorative Dentistry, Federal University of Santa Maria (UFSM), 1184 Floriano Peixoto Street, 3rd floor, 97015-372, Santa Maria, RS, Brazil. Electronic address: liligmay@gmail.com.
Abstract
OBJECTIVES: A systematic review of in vitro studies was conducted to assess the effect of thermal treatments on flexural strength or critical load to failure of porcelain-veneered zirconia (PVZ). SOURCES: Literature searches were performed up to June 2018 in PubMed/MEDLINE, Scopus and Web of Science databases, with no publication year or language limits. DATA: From 393 relevant studies, 21 were selected for full-text analysis, from which 7 failed to meet the inclusion criteria. The 14 remaining papers were included in the systematic review: 8 for meta-analysis and 6 restricted to descriptive analyses. Hand searching of reference lists resulted in no additional papers. STUDY SELECTION: In vitro studies using PVZ specimens testing the influence of thermal treatments on the fracture resistance to monotonic or cyclic loading. Papers evaluating cooling rate were divided into those applying fast cooling from above the porcelain glass transition temperature (Tg), or from below it. Meta-analyses were performed separately for flexural strength and critical load to failure, using random effects at a 5% significance level. CONCLUSIONS: Delaying furnace opening at a temperature below the porcelain Tg is advised for PVZ restorations, in order to improve their fracture resistance. Additional information is required to confirm the apparent beneficial effect of self-glaze and repeated veneer firings on the mechanical properties of these restorations. Finally, in order to obtain conclusive and relevant evidence regarding thermal treatments and the fracture resistance of PVZs, future studies should concentrate on anatomically-correct crown specimens.
OBJECTIVES: A systematic review of in vitro studies was conducted to assess the effect of thermal treatments on flexural strength or critical load to failure of porcelain-veneered zirconia (PVZ). SOURCES: Literature searches were performed up to June 2018 in PubMed/MEDLINE, Scopus and Web of Science databases, with no publication year or language limits. DATA: From 393 relevant studies, 21 were selected for full-text analysis, from which 7 failed to meet the inclusion criteria. The 14 remaining papers were included in the systematic review: 8 for meta-analysis and 6 restricted to descriptive analyses. Hand searching of reference lists resulted in no additional papers. STUDY SELECTION: In vitro studies using PVZ specimens testing the influence of thermal treatments on the fracture resistance to monotonic or cyclic loading. Papers evaluating cooling rate were divided into those applying fast cooling from above the porcelain glass transition temperature (Tg), or from below it. Meta-analyses were performed separately for flexural strength and critical load to failure, using random effects at a 5% significance level. CONCLUSIONS: Delaying furnace opening at a temperature below the porcelain Tg is advised for PVZ restorations, in order to improve their fracture resistance. Additional information is required to confirm the apparent beneficial effect of self-glaze and repeated veneer firings on the mechanical properties of these restorations. Finally, in order to obtain conclusive and relevant evidence regarding thermal treatments and the fracture resistance of PVZs, future studies should concentrate on anatomically-correct crown specimens.
Authors: Verena Preis; Christoph Letsch; Gerhard Handel; Michael Behr; Sibylle Schneider-Feyrer; Martin Rosentritt Journal: Dent Mater Date: 2013-05-30 Impact factor: 5.304
Authors: Camila da Silva Rodrigues; Iana Lamadrid Aurélio; Sara Fraga; Marina da Rosa Kaizer; Yu Zhang; Liliana Gressler May Journal: Dent Mater Date: 2021-04-15 Impact factor: 5.687
Authors: Fernando Zarone; Maria Irene Di Mauro; Pietro Ausiello; Gennaro Ruggiero; Roberto Sorrentino Journal: BMC Oral Health Date: 2019-07-04 Impact factor: 2.757